import urllib.parse

import bs4

# generate_nav(*, soup) → nav_tag
def generate_nav(*, soup):
	# TODO: Don't generate link to a board if we're at the index
	nav_tag = soup.new_tag('nav')

	for board in ['a', 'b', 'his', 'g']:
		# FIXME: Read this from a config file
		url = 'board/' + urllib.parse.quote(board, safe = '') + '/'
		a_tag = soup.new_tag('a', href = url)
		a_tag.string = '/' + board + '/'
		nav_tag.append(a_tag)

	return nav_tag

# generate_header(*, page_title, soup) → header_tag
def generate_header(*, page_title, soup):
	header_tag = soup.new_tag('header')

	h1_tag = soup.new_tag('h1')
	h1_tag.string = page_title
	header_tag.append(h1_tag)

	return header_tag

# generate_footer(*, soup) → footer_tag
def generate_footer(*, soup):
	# TODO: Add footer generation
	return soup.new_tag('footer')

# page_skeleton(*, page_title, contents, soup) → html
# Given page title (string) and contents (iteratable of beautifulsoup tags), create the html
# Since most pages have same basic structure, it makes sense to factor this out from page creation functions
def page_skeleton(*, page_title, contents, soup):
	# Doctype and head are more or less the same for each page, no need to do anything fancy when adding them
	soup.append(bs4.Doctype('html'))

	head_tag = soup.new_tag('head')
	title_tag = soup.new_tag('title')
	title_tag.string = page_title
	head_tag.append(title_tag)
	soup.append(head_tag)

	# Body consists of (more or less same) header and footer, and varying content
	body_tag = soup.new_tag('body')

	body_tag.append(generate_nav(soup = soup))
	body_tag.append(generate_header(page_title = page_title, soup = soup))

	# contents is an iterable that can contain several tags
	for tag in contents:
		body_tag.append(tag)

	body_tag.append(generate_footer(soup = soup))

	soup.append(body_tag)

	# Use .prettify() to generate nice-looking HTML
	# We are probably never going to serve enough pages for the additional whitespace to count for data usage
	return soup.prettify()

# new_soup() → soup
# Since we need a soup object to create tags, split this from page_skeleton
def new_soup():
	# Use python's built-in parser for portability
	# We'll be constructing the document programmatically, so start with empty tree
	soup = bs4.BeautifulSoup('', 'html.parser')

	return soup

# board() → html
# Creates the board index page
def board(board_name):
	# TODO: Creae a board index page
	soup = new_soup()

	page_title = '/' + board_name + '/'

	return page_skeleton(page_title = page_title, contents = [], soup = soup)

# index() → html
# Create the site index
def index():
	# TODO: Create an index page
	soup = new_soup()
	return page_skeleton(page_title = 'Buranun', contents = [], soup = soup)

# error_404(path) → html
def error_404(path):
	soup = new_soup()

	p_tag = soup.new_tag('p')
	p_tag.string = path + ' does not exist'

	return page_skeleton(page_title = '404 Not Found', contents = [p_tag], soup = soup)